Intraocular pressure in subjects with beta-thalassemia minor / Pressão intraocular em indivíduos com talassemia beta minor

ABSTRACT Purpose: Beta-thalassemia minor, a common hereditary blood disorder in Mediterranean countries such as Turkey, is associated with insulin resistance. Insulin resistance, in turn, can be associated with excessively high intraocular pressure and, therefore, intraocular pressure-induced blindness. This study aimed to investigate the intraocular pressure in subjects with beta-thalassemia minor. Methods: We conducted a cross-sectional study comprising of 203 subjects divided into two groups: beta-thalassemia minor (103) and healthy (100).Hemoglobin electrophoresis was performed and complete blood count, blood pressures, serum fasting glucose and insulin levels were measured. All subjects underwent ophthalmological examinations including intraocular pressure measurements. Results: Intraocular pressure in the subjects with beta-thalassemia minor was significantly lower than that in healthy subjects (p=0.007). Additionally, intraocular pressure was inversely correlated with hemoglobin A2 levels (p=0.001, r=-0.320). Serum insulin and systolic blood pressure were significantly higher in subjects with beta-thalassemia minor (p=0.03, p=0.009, respectively). Conclusion: Subjects with beta-thalassemia minor had lower intraocular pressure than healthy controls, suggesting beta-thalassemia minor may actually protect against high intraocular pressure.

RESUMO Objetivo: Beta-talassemia menor é uma doença hereditária comum no sangue em países mediterrâneos como a Turquia e está associada à resistência à insulina. A resistência à insulina por sua vez, pode estar associada à pressão intraocular excessivamente alta e, portanto à cegueira induzida pela pressão intraocular. Este estudo teve como objetivo investigar a pressão intraocular em indivíduos com beta-talassemia menor. Métodos: Foi realizado um estudo transversal compreendendo 203 indivíduos divididos em 2 grupos: beta-talassemia menor (103) e saudável (100). Eletroforese de hemoglobina foi realizada e hemograma completo, pressão arterial, glicemia em jejum e níveis de insulina medidos. Todos os indivíduos foram submetidos foram submetidos a exames oftalmológicos, incluindo medidas de pressão intraocular. Resultados: A pressão intraocular nos indivíduos com beta-talassemia menor foi significativamente menor do que em indivíduos saudáveis (p=0,007). Além disso, a pressão intraocular foi inversamente correlacionada com os níveis de hemoglobina A2 (p=0,001, r=-0,320). Insulina sérica e pressão arterial sistólica foram significativamente maiores em indivíduos com beta-talassemia menor (p=0,03, p=0,009, respectivamente). Conclusão: Os indivíduos com beta-talassemia menor tiveram pressão intraocular menor do que os controles saudáveis, sugerindo que a beta-talassemia menor pode, na verdade, proteger contra a alta pressão intraocular.

Intraocular pressure in subjects with beta-thalassemia minor.

PURPOSE: Beta-thalassemia minor, a common hereditary blood disorder in Mediterranean countries such as Turkey, is associated with insulin resistance. Insulin resistance, in turn, can be associated with excessively high intraocular pressure and, therefore, intraocular pressure-induced blindness. This study aimed to investigate the intraocular pressure in subjects with beta-thalassemia minor. METHODS: We conducted a cross-sectional study comprising of 203 subjects divided into two groups: beta-thalassemia minor (103) and healthy (100).Hemoglobin electrophoresis was performed and complete blood count, blood pressures, serum fasting glucose and insulin levels were measured. All subjects underwent ophthalmological examinations including intraocular pressure measurements. RESULTS: Intraocular pressure in the subjects with beta-thalassemia minor was significantly lower than that in healthy subjects (p=0.007). Additionally, intraocular pressure was inversely correlated with hemoglobin A2 levels (p=0.001, r=-0.320). Serum insulin and systolic blood pressure were significantly higher in subjects with beta-thalassemia minor (p=0.03, p=0.009, respectively). CONCLUSION: Subjects with beta-thalassemia minor had lower intraocular pressure than healthy controls, suggesting beta-thalassemia minor may actually protect against high intraocular pressure.

[Phenotyping and genotyping studies in a family with the compound heterozygosity deltabeta Thalassemia/beta(IVSII-849) Thalassemia]. / Fenotipo y genotipo del doble heterocigoto para deltabeta Talasemia/beta(IVSII-849) Talasemia en una familia venezolana.

The propositus is a two year old child with a severe hemolytic anemia and increased level of Hb F. The Hbs A, A2 and F were eluted and quantitated by cation exchange high-performance liquid chromatography (HPLC-CE). DNA was isolated from peripheral blood leukocytes by a salting-out extraction procedure. The beta globin gone was amplified and the presence of the beta thalassemia mutation was determined by PCR followed of Reverse Dot Blot. Her hematological parameters were as follows: Hb: 7.0 g/dL, Hct: 24.8%, VCM: 87.4 fl, CHCM: 27.8 fl. The haemoglobin study showed an 97% increase of Hb F and Hb A2 normal. The molecular study suggested the presence of beta(IVSII-829) mutation in trans to deltabeta Thalassemia. The propositus inherited her mother's deltabeta-thalassemia gene mutation and her father's beta(IVSH-829) mutation. This is the first time the diagnosis has been performed in a Venezuelan family at-risk of compound heterozygotes for beta-thalassemia and delta beta-thalassemia.

Hematologic study of newborn umbilical cord blood.

Hematological parameters in newborn umbilical cord blood samples (n = 476), collected at the Hospital Provincial del Centenario, Rosario, were studied. They were divided into 3 groups: (I) full term newborns with weight according to gestational age; (II) low weight and normal gestational age; (III) preterm newborns. The results were as follows: group (I) Hb: 15.5 +/- 1.1 g/dl; RBC; 4.66 +/- 0.33 x 10(12)/l; PCV: 49% +/- 4.3%, MCV 105.1 +/- 5.3 fl; MHC: 33.2 +/- 1.2 pg. Decreased Hb concentration (p < 0.05) and increased MCV (p < 0.01) were observed in preterm newborns in comparison with normal ones, and a slight PCV increase and RBC values in low weight newborns compared to the control group (p < 0.05). Erythrocyte morphology was normal as well as reticulocyte values in these samples. The electrophoretic pattern was (FA) with the following Hb F values 66.3 +/- 6.8%, and Hb A2 0.45 +/- 0.3% in group (I), with a significant increase of Hb F in 30-35 weeks preterm newborns. Group (I) values are considered as normal hematological parameters in newborns in our country, whereas MCV < 94.7 fl is considered as a neonatal microcytosis marker, consequently an alert to investigate alpha-thalassemia. There was no influence on Hb concentration due to maternal smoking habit. The present work could be of relevance for our region since up to the present time there are no similar records.

Hematologic study of newborn umbilical cord blood

Hematological parameters in newborn umbilical cord blood samples (n=476), collected at the Hospital Provincial del Centenario, Rosario, were studied. They were divided into 3 groups: (I) full term newborns with weight according to gestational age; II) low weight and normal gestational age; (III) preterm newborns. The results were as follows: group (I) Hb: 15.5 + 1.1 g/dl; RBC: 4.66 + 0.33 x 1012/I; PCV:49 + 4.3 percent, MCV 105.1 + 5.3 fl; MHC: 33.2 + 1.2 pg. Decreased Hb concentration (p<0.05) and increased MCV (p<0.01) were observed in preterm newborns in comparison with normal ones, and a slight PCV increase and RBC values in low weight newborns compared to the control group (p<0.05). Erytrocyte morphology was normal as well as reticulocyte values in these samples. The electrophoretic pattern was (FA) with the following Hb F values 66.3 + 6.8 percent, and Hb A2 0.45 + 0.3 percent in group (I), with a significant increase of Hb F in 30-35 weeks preterm newborns. Group(I) values are considered as normal hematological parameters in newborns in our country, whereas MCV< 94.7 fl is considered as a neonatal microcytosis marker, consequently an alert to investigate alpha-thalassemia. There was no influence on Hb concentration due to maternal smoking habit. The present work could be of relevance for our region since up to the present time there are no similar records.

Hematologic study of newborn umbilical cord blood

Hematological parameters in newborn umbilical cord blood samples (n=476), collected at the Hospital Provincial del Centenario, Rosario, were studied. They were divided into 3 groups: (I) full term newborns with weight according to gestational age; II) low weight and normal gestational age; (III) preterm newborns. The results were as follows: group (I) Hb: 15.5 + 1.1 g/dl; RBC: 4.66 + 0.33 x 1012/I; PCV:49 + 4.3 percent, MCV 105.1 + 5.3 fl; MHC: 33.2 + 1.2 pg. Decreased Hb concentration (p<0.05) and increased MCV (p<0.01) were observed in preterm newborns in comparison with normal ones, and a slight PCV increase and RBC values in low weight newborns compared to the control group (p<0.05). Erytrocyte morphology was normal as well as reticulocyte values in these samples. The electrophoretic pattern was (FA) with the following Hb F values 66.3 + 6.8 percent, and Hb A2 0.45 + 0.3 percent in group (I), with a significant increase of Hb F in 30-35 weeks preterm newborns. Group(I) values are considered as normal hematological parameters in newborns in our country, whereas MCV< 94.7 fl is considered as a neonatal microcytosis marker, consequently an alert to investigate alpha-thalassemia. There was no influence on Hb concentration due to maternal smoking habit. The present work could be of relevance for our region since up to the present time there are no similar records. (AU)

Diferenciaçäo entre talassemia beta-heterozigótica e anemia ferropriva / Differentiation between heterozygotic beta-thalassemia and iron deficiency anemia

Várias funcöes discriminantes baseadas nos parâmetros hematimétricos fornecidos pelos contadores eletrônicos de células têm sido desenvolvidas e utilizadas nas diferenciaçäo de várias formas de anemia. A eficiência de alguns desses critérios comumente empregados na distinçäo entre a talassemia beta-heterozigótica e a anemia ferropriva foi testada em 192 indivíduos talassêmicos e em 72 adultos com anemia ferropriva. Foram avaliados: 1) funçäo discriminante de England e Fraser: VCM - (5xHb) - H - 8,4;2) HCM/H; 3) relaçäo de Mentzer: VCM/H; 4) (VCM)² x HCM; e 5) número de hemácias. Os resultados obtidos demonstraram falha na distinçäo entre estas duas entidades, em percentagens variáveis de 9 a 90//, sendo que a equaçäo de England e Fraser demonstrou os resultados mais satisfatórios, enquanto a relaçäo de Mentzer apresentou maiores índices de erro no diagnóstico da anemia ferropriva. Assim, embora algumas dessas fármulas possam ser utilizadas em programa de triagem, em casos individuais a diferenciaçäo entre talassemia beta-heterozigótica e anemia ferropriva deve ser sempre realizada com dosagens de HbA2, ferro sérico, capacidade máxima de transporte de ferro e ferritina

[Differentiation between heterozygotic beta-thalassemia and iron deficiency anemia]. / Diferenciação entre talassemia beta-heterozigótica e anemia ferropriva.

Several laboratory tests have been proposed for the differentiation of beta thalassemia from iron deficiency, including decision functions based on red blood cells indices generated by electronic cell counters. The accuracy of these screening methods was assessed in 192 patients with microcytosis known to be secondary to beta thalassemia minor and 72 patients with iron deficiency. The functions evaluated were: 1) discriminant function of England an Fraser: MCV--(5xHb)--RBC--8.4; 2) ratio of MCH/RBC; 3) ratio of MCV/RBC; 4) ratio of (MCV)2 x MCH and 5) the erythrocyte count. The discriminant function of England and Fraser showed the highs, percentage of correct distinction between iron deficiency and beta thalassemia minor, although diagnosis errors occurred in 10%. Mentzer ratio MCV/RBC detected all cases of beta thalassemia but was a poor index for iron deficiency detection. The tested discriminant function, with exception of the Mentzer ratio, although not sufficiently accurate for definitive diagnosis, appears to be a useful technique in the initial screening of patients with microcytosis.

Frecuencia de beta-talasemia en pacientes atendidos en el hospital hermanos Ameijeiras / Frecuency of beta-thalassemia in patients assisted at the Hermanos Ameijeiras hospital

Se estudia una muestra de 1 010 pacientes no hematológicos, en la cual se determinó el volumen corpuscular medio, el fenotipo electroforético de hemoglobina y en los casos que así lo requirieron, se cuantificó la hemoglibina A2. Se consideró la coexistencia de microcitosis y hemoglobina A2 elevada como criterio para la identificación de personas que padecen de beta-talasemia. Los resultados obtenidos permiten concluir que existe una frecuencia de 0,69 % + 0,01 para este rasgo hereditario

Estigma beta talassemico em uma amostra da populaçao de Natal, RN / Beta thalassemia trait in a sample from the population of Natal,RN

Foi realizado um estudo com objetivo de determinar a prevalencia de talassemia beta em uma amostra da populaçao da cidade de Natal,RN. Foram analisadas 1.106 amostras de sangue de individuos de ambos os sexos e diferentes faixas etarias. Os sangues foram coletados por punçao venosa,adicionados a EDTA e analisados mediante o teste de fragilidade osmotica em soluçao de NaC1a0,36%.As amostras que apresentaram teste positivo foram submetidas a eletroforese quantitativa para dosagem de HbA2 e a determinaçao bioquimica da hemoglobina fetal por desnaturaçao alcalina. Dentre os individuos estudados, foram identificados 19 com traço talassemico beta representando uma prevalencia em torno de 1,72%.

A greater than 200 kb deletion removing the entire beta-like globin gene cluster in a family of Irish descent.

We describe a new deletional form of gamma delta beta-thalassemia segregating in two generations of a family of Irish descent. Affected family members present with a beta-thalassemia minor phenotype, normal Hb A2 and Hb F levels. Genomic blotting analyses on DNA from affected family members show heterozygosity for a large deletion beginning at least 15 kb upstream of the 5' endpoint of the gamma delta beta-thalassemia-1 deletion, extending through the entire beta-like globin gene cluster, and continuing for at least 10 kb beyond the 3' endpoint of the deletion associated with the Spanish form of delta beta 0-thalassemia. This deletion is among the largest described so far, and removes at least 205 kb encompassing the entire beta-like globin gene cluster on chromosome 11.

Comparison of homozygous sickle cell disease in northern Greece and Jamaica.

The clinical and haematological features of homozygous sickle cell (SS) disease were compared in 30 Greek and 310 Jamacian patients. Deletional alpha-thalassaemia, which modifies SS disease, is rare among Greek patients, so only Jamacian patients with four alpha-globin genes were included in the control group. Greek patients had higher total haemoglobin concentration and red cell counts, and lower mean cell haemoglobin concentration (MCHC) and reticulocyte counts. They also had a more normal body build and more adults had persistent splenomegaly. Fewer had a history of leg ulceration or priapism but more reported acute chest syndrome. The comparatively mild disease in Greek patients is consistent with less haemolysis and sickling and therefore less bone marrow expansion. In the absence of amelioriating factors such as high HbF concentration or alpha-thalassaemia, these findings may be explained by the low MCHC.

[A comparison of methods for the determination of A2 hemoglobin]. / Comparación de métodos para la cuantificación de hemoglobina A2.

Three different methods to assess haemoglobin A2 concentration (microchromatography and cellulose acetate electrophoresis with further elution of the bands or measured by densitometry) were compared among them. A statistical significant difference (P less than 0.05) was found between densitometry and the other two methods. Microchromatography and the elution method showed no statistical difference between them. The most important technical aspects of each method as well as some possible error factors were also discussed.

Comparison of homozygous sickle cell disease in Northern Greece

The clinical and hematological features of homozygous sickle cell (SS) disease were compared in 30 Greek and 310 Jamaican patients. Deletional O-thallassaemia, which modifies SS disease, is rare among Greek patients, so only Jamaican patients with four O-globin genes were included in the control group. Greek patients had higher total haemoglobin concentration and red cell counts, and lower mean cell haemoglobin concentration (MCHC) and reticulocyte counts. They also had a more normal body build and more adults had persistent splenomegaly. Fewer had a history of leg ulceration or priapism but more reported acute chest syndrome. The comparitively mild disease in Greek patients is consistent with less haemolysis and sickling and therefore less bone marrow expansion. In the absence of amelioriating factors such as high HbF concentration or O-thalassaemia, these findings may be explained by the low MCHC. (AU)

Hematological and biochemical studies in children with Down syndrome.

Eighty-three children with Down syndrome were submitted to hematological and biochemical studies; 69 normal children were included as controls. The variables analyzed were: HbF, HbA2, serum B12 vitamin (B12), folates, total iron and iron binding capacity, hematic cytology, and the red blood cell enzymes adenosine deaminase (ADA), glucose-6-phosphate dehydrogenase (G6PD) and superoxide dismutase (SOD). The most relevant results were: macrocytosis, normal leucocytes, HbF, B12 and folates, as well as high levels of the enzymes ADA and G6PD. An indirect association between macrocytosis, ADA and G6PD is discussed.

Hormonas tiroideas y niveles de hemoglobina A2 y hemoglobina fetal / Thyroid hormones and hemoglobin A2 and fetal hemoglobin levels

Se estudió el patrón electroforético, los niveles de hemoglobina A2, hemoglobina fetal, hemoglobina, hematocrito, eritrocitos, reticulocitos e hierro sérico en 85 pacientes del sexo femenino con diversos trastornos tiroideos, no tratadas, no anémicas con edades comprendidas entre 15 y 71 años, las cuales fueron divididas en los siguientes grupos: Grupo I constituido por 26 pacientes hipertiroideas; Grupo II,9 pacientes con hipotiroidismo; Grupo III,26 pacientes con bocio nodular y grupo IV 24 pacientes con bocio difuso simple. Previamente se estudió un grupo de referencia constituido por 36 mujeres aparentemente sanas sin evidencias clínicas y/o de laboratorio de padecer trastornos tiroideos, este grupo se clasificó como grupo V. Se concluye que aún cuando se observan discretas, variaciones en los valores promedio de hemoglobina A2 en los pacientes hipertiroideos e hipotiroideos y de hemoglobina fetal en los pacientes hipertiroideos, las mismas se mantuvieron dentro del rango normal por lo que su determinación no es discriminatoria en el diagnóstico de dichas patologías

Hemoglobina A2 e hemoglobina total / Hemoglobin A2 and total hemoglobin

Em 518 indivíduos (210 homens e 308 mulheres) residentes em Salvador, Bahia, com dosagens de hemoglobina F inferior a 2,5%, foram analisados os resultados de hemoglobina A2 e de hemoglobina total. A média de hemoglobina A2 para os homens foi de 3,0% e para as mulheres 2,7%. Para a amostra em estudo o limite máximo de normalidade para a hemoglobina A2 foi até 5,5%. A percentagem de produçäo de hemoglobina A2 näo estava na dependência do sexo, porém era inversamente proporcional à quantidade de hemoglobina total

Variantes de hemoglobina A2 / Hemoglobin A2 variants

Foram analisados sete casos com variantes de hemoglobina A2 (2 homens e 5 mulheres). Os homens e mulheres com variantes de hemoglobina A2 apresentaram valores de hematócrito e hemoglobina semelhantes aos estigmas AS e AC

Prevalências de talassemia alfa em pacientes com anemia e em pessoas sem anemia / Prevalence of alpha thalassemia in patients with anemia and in individuals without anemia

Foram analisadas amostras de sangue de 400 pessoas residentes em Säo José do Rio Preto. Desse total, 195 foram obtidas de pacientes com anemia sem causa definida e 205 de indivíduos aparentemente sadios. O diagnóstico de talassemia alfa foi realizado por meio da pesquisa citológica de agregados intra-eritrocitários de Hb H. Esse teste indicou que, no grupo de pacientes com anemia sem causa definida, 15,89% tinham talassemia alfa. No grupos controle, composto por pessoas aparentemente sadias, 3,90% eram portadoras de talassemia alfa. A avaliaçäo hematimétrica constituída por contagem de eritrócitos, hematócrito, hemoglobina e índices hematimétricos, mostraram que os portadores de talassemia alfa apresentavam diferenças quantitativas em comparaçäo com o grupo de controle. Alteraçöes na morfologia eritrocitária foram observadas em 48% dos portadores de talassemia alfa extraídos do grupo de pacientes com anemia, enquanto que entre aqueles diagnosticados no grupo controle, 25% apresentavam modificaçöes na morfologia eritrocitária. Os valores de Hb A2 e Hb Fetal näo apresentaram diferenças importantes entre os grupos estudados